Observed failures running with P9 mambo model, and figured out that the
xer wasn't initialized.

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
---
 risugen_ppc64.pm | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/risugen_ppc64.pm b/risugen_ppc64.pm
index 0532e3a..03f9317 100644
--- a/risugen_ppc64.pm
+++ b/risugen_ppc64.pm
@@ -168,6 +168,9 @@ sub clear_vr_registers()
     insn32(0x3ac10020);
     # li r23, 0
     write_mov_ri(23, 0);
+    # zero the xer register
+    # mtxer   r23
+    insn32(0x7ee103a6);
     # std r23, 0(r22)
     insn32(0xfaf60000);
 
-- 
2.7.4